Collaborative Research: Extending leaf functional trait ecology to leaf symbionts

丰富多样的真菌生活在所有树木的健康叶片中。这些“真菌内生菌”（endo，inside; phyte，plant）在胁迫条件下对增强植物健康很重要。然而，在不同的植物物种中发现的内生菌的多样性社区的形状的因素还没有得到很好的理解。该项目的总体目标是将真菌内生菌整合到我们对热带植物生态学的理解中，特别关注叶片性状，植物生产力以及植物抵御昆虫和病原体攻击叶片的能力之间的关系。 提高我们对真菌内生菌的理解是重要的，因为它们影响植物的生产力和对环境胁迫如干旱和疾病的抗性，包括对具有经济重要性的植物。研究结果将有助于利用内生菌缓解植物对快速变化的世界的反应，并在可持续农业和森林管理中具有潜在的应用。 该项目还将支持对本科生和研究生进行跨学科研究的培训，包括代表性不足群体的学生，为K-12教师和高中生提供指导性研究经验，并促进公共宣传。本项目将检验以下假设：（1）叶片中的内生菌群落与叶片性状有关，这些性状与生长和持久性策略有关;（2）内生菌将影响叶片和植物功能;（3）内生菌对植物防御的贡献将作为叶性状的函数而变化;和（4）通过整合这些叶共生体可以极大地了解植物的生长与持久性策略。研究方法包括实地观察和实验以及生物测定。计划进行田间实验，其中在12个焦点物种中操纵内生菌群落。此外，来自这12个物种的叶子将被引入切叶蚁，以测试寿命较长的物种是否对切叶蚁不那么有吸引力，以及这是否会由内生菌负载介导。此外，病原体将被引入到12个焦点物种中，以测定在具有高内生菌负载的叶子中损害是否会较低。

Abundant and diverse fungi live inside healthy leaves of all trees. These 'fungal endophytes' (endo, inside; phyte, plant) can be important in enhancing plant health under stressful conditions. However, the factors that shape the diverse communities of endophytes found in different plant species are not well understood. This project's overall goal is to integrate fungal endophytes into our understanding of tropical plant ecology, with a special focus on the relationships among leaf traits, plant productivity, and the ability of plants to defend against insects and pathogens that attack leaves. Improving our understanding of fungal endophytes is important since they influence plant productivity and resistance to environmental stresses such as drought and disease, including for plants of economic importance. Results will facilitate use of endophytes in mitigating plant responses to a rapidly changing world, with potential applications in sustainable agriculture and forest management. This project will also support the training of undergraduate and graduate students in interdisciplinary research, including students of under-represented groups, provide mentored research experiences for K-12 teachers and for high school students, and contribute to public outreach.In the context of tropical forests, where leaf traits and endophytes are highly diverse, this project will test the hypotheses that (1) endophyte communities in leaves vary in relation to leaf traits associated with growth vs. persistence strategies; (2) endophytes will influence leaf and plant functions; (3) contribution of endophytes to plant defense will vary as a function of leaf traits; and (4) understanding growth vs. persistence strategies of plants can be informed greatly by integration of these foliar symbionts. The research approach involves field observations and experiments as well as bioassays. A field experiment is planned where endophyte communities are manipulated in 12 focal species. Additionally, leaves from these same 12 species will be introduced to leaf cutter ants to test whether longer lifespan species are less attractive to leaf cutter ants, and whether this will be mediated by endophyte load. Furthermore, pathogens will be introduced to the 12 focal species to assay if damage will be lower in leaves with high endophyte loads.